1. Field of the Invention
The present invention refers to a chair with a tilting backrest.
More precisely, the invention refers to a chair comprising a base structure bearing a seat, and a backrest connected to the base structure by means of two side joints that allow a movement of the backrest between a rest position and a backward tilted position under a backwards push applied by the user.
2. Description of the Related Art
In the state of the art, several solutions are known for obtaining a backward tilting movement of the backrest under a backwards push applied by the user.
For example, the document EP-A-1557115 by the same applicant describes a chair with a tilting backrest connected to the base structure by means of elastically yieldable side connecting components to allow backward tilting of the backrest.
Another known solution is described in document EP-A-2183997, in which the backrest is connected to the base structure by means of two elastic devices, each of which is formed by an elastic component, deformable by bending, and inserted within a plurality of stacked sectors.
One of the problems of the known solutions is that the centre of rotation of the backrest during the backward tilting movement does not coincide with the centre of rotation of the user's back. This means that during the backward tilting movement of the backrest there is a relative movement between the base surface of the backrest and the user's back. This relative movement tends to cause pulling-out of clothes.
For example, if the user is wearing a shirt tucked into his trousers, in the known chair types, the backward tilting movement of the backrest tends to pull out the shirt from his trousers.